The National Capital is predicted to hit a heavy weather milestone after the India Meteorological Department (IMD) predicts a wet spell commencing today and reaching maximum on January 23, 2026. Prompted by a vigorous Western Disturbance moving through the Northwest of the region, the rainfall will be a welcome relief as well as a fresh winter challenge for Delhi-NCR residents.
The Prediction: Rain, Thunder and Gusty breeze
By Thursday evening, the IMD's latest bulletin stated Delhi will rise from partly misty skies to a mostly cloud-filled ceiling. The main weather is predicted to be Friday, 23 January and will see:
- Light to Moderate Rain: One or two showers are expected on the outside around the city and close neighbours such as Noida, Gurugram and Ghaziabad.
- Thunderstorms & Lightning: Isolated areas might be under electrical loads.
- Gusty Winds: surface winds are forecast between 30 and 40 kmph, which are going to be disruptive to some extent but not much else, will help get rid of dead air.
AQI: Is the Rain Getting Rid of the Smog?
Delhi: For weeks, Delhi has been living near the low end of 'Very Poor'; air quality ranges from ‘Very Poor’ to ‘Severe’ with AQI often around the 400 mark. Meteorologists say the next day's rain might serve as natural "scrubbing" agents.
“The ‘Washout’ Effect:”
Rainfall is credited to settling suspended particulate matter ($PM_{2.5}$ and $PM_{10}$) which would help settle the air as airborne particle from the air and would push the AQI down to moderate/poor.
- Wind Dispersion: The blowback winds are critical. Strong wind is also important, whether or not the rain falls bitterly or sodden as they are in the other places.
- Temperature: The resurgence of the 'Winter Chill'
Even if it’s a little bit of rain, strong winds will scatter these pollutants left behind by inadequate ventilation near the surface.
Temperature: The ‘Winter Chill’ Once again
But the rain is going to keep the air clean, and its effect will intensify the cold.
- Day-time Dip: After showers peak temperatures, which had reached a comfortable level of 24-26°C, are going to fall to 19-21°C.
- The Chill Factor: While the winter chill factor can be briefly increased to, for example, 12-14°C in short bursts because of cloud cover trapping heat (greenhouse effect), the high humidity and the cold, near northwesterly winds from snowbound Himalayas will likely exacerbate the cooling factor (the ”real feel” effect) significantly.
Western Disturbance Impacts Outside of Delhi
In Delhi, the effect of the system is more far-reaching (the system cannot be confined to the capital). The IMD has also issued alerts as follows:
- Heavy Snowfall: January 23, in the upper reaches of Himachal Pradesh and Uttarakhand
- Hailstorms: May occur in remote regions of Punjab and Haryana.
Advisory for Residents
Visibility is due to drop under rain and lead to morning fog on January 24 and commuters need to:
- Check Flight/Train Status: Rain and fog may cause delays at IGI Airport and major railway stations.
- Health Precautions: Variations in temperature (from a warm 25°C to a wet 19°C) are a key factor behind the seasonal flu crisis; residents should abide by respiratory hygiene.
- Driving Safety- Avoid using high beam headlights on the DND Flyway and Yamuna Expressway (there’s a high crosswind risk).
